Operation and use
Static mixers are elements which are placed in a pipe or tube so different components can flow through it. Because the currents have to follow the shape of the static mixer they are mixed together. This all happens without using any moving parts, hence the term static mixers.
The development of static mixers has a long history. Since their invention, ca. 1900, there have been hundreds of different designs developed by many companies, institutes, and universities aiming to develop the ‘perfect’ static mixer. Some designs are almost identical to the original design from 1900, apparently right away a good design, other designs have only come about recently after much research and many calculations (using CFD – Computer Fluid Design).
These days every application has a best static mixer shape. After all, the best static mixer generates the lowest possible pressure drop using the shortest possible insertion length and generates the highest possible mixing efficiency.
A lot of money can be saved during its long lifespan by using the right static mixer. After all they operate “statically” and when used to mix components that are both non-abrasive and non-corrosive the lifespan is in principle infinitely long.
However, cleaning durable mixers can be impractical, expensive, or error-prone. That is why nowadays there are also disposable static mixers that can be replaced by a new and sterile copy after a day of mixing. These mixers are a lot cheaper as they only have to last for a short period of time.
Classical mixing processes
- Liquid (L) / liquid (L)
- Gas (G) / liquid (L)
- Gas (G) / Gas (G)
- Solids (S) / liquid (L)
- Solids (S) / solids (S)